Wire cords



Jan. 9, 1968 G. CURTIS 3,362,147

" WIRE CORDS Filed. May 27, 1965 2 Sheets-Sheet 1 Inventor k GEOFFREY CURVE Attorneys Jan. 9, 1968 v G. CURTIS 3,362,147

WIRE CORDS Fi led. May 27, 1965 2 Sheets-Sheet 2 F IG 4 [nvenlor GEOFFREY GURUS A tlorneys United States Patent Ollice 3,3fi2,147 Patented Jan. 9, 1968 3,362,147 WIRE CORDS Geoffrey Curtis, Coventry, England, assiguor to Steel Cords Limited, London, England, a British company Filed May 27, 1965, Ser. No. 459,415 Claims priority, application Great Britain, June 2, 1964, 22,727/64 14 Claims. (Cl. 5734) ABSTRACT OF THE DISCLOSURE Method and apparatus for the production of wire cords such as are used for reinforcement of tyres in which the component wires are initially wound in groups of from two to six Wires on separate bobbins. The groups are then drawn from the bobbins, the wires of the groups being separated as necessary and then being laid in the desired relation before twisting to form the cord.

This invention relates to wire cords such as are used for reinforcement of tyres and other articles of rubber or plastics.

A wire cord is usually produced from two or more wires, each wound on separate bobbins, by drawing the wires from the bobbins through straightening and twisting devices and winding the cord on a take-up reel. A separate spindle is thus required for each bobbin together with guides for leading each wire from its bobbin to the straightening and twisting devices.

According to this invention the wires of two or more wire groups, each of a number of wires between two and six inclusive wound on a single bobbin, are led simultaneously from their bobbins through a twisting device which forms them together into a cord to a take-up device.

The wires of each wire group are preferably twisted together so as to keep the wires of each group together in each turn on the bobbin. This may simply be a winding twist which may be removed on unwinding by drawing the group of]? over the end of the bobbin in the appropriate sense.

The wires of each group may be wound on the bobbin directly from a number of separate bobbins each carrying a single wire, or preferably, are wound on the bobbin directly from a multi-end wire-drawing machine as described in the specification of British Patent No. 976,572. The cord can then be produced in a two-stage operation, in the first stage of which groups of wires are drawn and wound simultaneously, and in the second of which the wires of a number of groups so wound are brought together, twisted and wound as a cord.

Furthermore, by use of the present invention cordmaking apparatus can be simplified in that all the wires for a multiple wire cord are carried in groups on a number of bobbins considerably less than the number of wires. For example a 15 wire cord can be produced by using only 5 bobbins, each of which carries a group of 3 wires.

The wires of the groups may simply be passed directly to the twisting device which forms the cord through a guide eye or, particularly for producing a cord from a large number of groups, they may be passed through a lay plate or like guide before the twisting device so as to arrange them in a particular manner before they reach the twisting device.

Use of an assembly or pulleys in place of a lay plate is advantageous as by this means friction and distortion, which can occur with wires drawn under tension over the edges of lay plate holes, may be decreased. Any unevenness in tension between various wires in a group may be minimised by use of a pulley assembly.

The wires of the two or more groups may be twisted together with one or more single wires to make up the desired number of wires in the finished cord. For ex ample a single wire may be used as a core around which the groups of wires are twisted.

Further examples of cords which may be constructed by use of the invention are:

(a) 13 wires, using one bobbin carrying a group of four wires and three bobbins each carrying a group of three wires.

(b) 10 wires, using one bobbin carrying a group of two wires and two bobbins each carrying a group of :four wires.

(c) 21 wires, using three bobbins carrying groups oi four wires (one of which may form an inner core) and three bobbins carrying three wires (which may be wrapped around the other twelve wires).

Some or all of the wires of each group are preferably passed through separate holes in a lay plate, through separate guides or over separate pulleys. For example, in the ten-wire cord mentioned above the wires of the group of two are passed through two spaced holes in the middle of the lay plate, and the wires of the other two groups are passed through holes in a ring of eight holes around the two inner holes so that the wires are assembled prior to the twisting device as a group with eight wires clustered around two. The two inner wires nest together as a core and the eight outer wires are laid upon the core in two groups. If desired the two wires forming the core may be passed through a single central hole in the lay plate.

An example of apparatus for carrying out the invention is illustrated by the accompanying drawing, in which:

FIGURE 1 is a diagrammatic side elevation of the apparatus.

FIGURE 2 is a plan of part of the apparatus.

FIGURE 3 is an elevation of a lay plate for producing one particular cord, and

FIGURE 4 is a diagrammatic elevation of an assembly of pulleys for producing another particular cord.

The apparatus comprises a number of mountings 1 for bobbins 2, each carrying the group of wires between two and six, inclusive, in number. The number of mountings required depends upon the cord to be produced and the number of wires in each group, but for convenience only one is shown. There'may also be mountings (not shown) for one or more bobbins carrying single wires which may be required in conjunction with the groups for making up the required cord.

In the embodiment illustrated, the wires 3 of the group, four in number, are twisted together on the bobbin 2 with winding twist, and the mounting 1 supports the bobbin 2 in an upright stationary position so that the wires are drawn ofi over-end over a flyer pulley in a sense such as to remove the winding twist.

The untwisted wires 3 of the group pass together from the fiyer 4 over a stationary guide pulley 5, and are separated, to ensure that all twist a removed from the group and to prevent any twist later imparted to the wires from travelling back to the bobbin 2, by a pair of guide pins 6, and then are brought together again and passed in one or more complete turns around a free running pulley 7, which also serves to restrict backward travel of twist later imparted to the wires.

The parts of the apparatus so far described are duplicated for each group of wires required to make up the desired wire cord. As mentioned there may also be mountings for bobbins carrying single wires. These wires will simply be passed over a guide pulley and thence to the lay plate with the groups as will be described.

From the pulleys 7 (and the guide pulleys if any in the case of single wires) the wires 3 pass individually v. through holes in a stationary lay plate 8 and are then drawn together to pass through a die 9 which nests the wires together in the position determined by the lay plate.

From the die 9 the nested wires pass in one or more complete turns over a lay pulley 10 mounted in a cradle 11 which is rotated about the axis of the lay plate 8 and die 9 at a speed determined in relation to the speed at which the wires pass through the apparatus (as determined by the speed of the take-up bobbin, as will be described) such as to produce the lay which is desired in the wires in the finished cord. The twisted wires then pass to a torsioning capstan, comprising two pulleys 12 mounted in a cradle 13 which, like the cradle 11, is rotated about the axis of the lay plate 8 and die 9. The wires are passed in at least one complete figure of eight around the pulleys 12 and the cradle 13 is driven at a speed in excess of the speed of the cradle 11 such as to provide the necessary degree of torsioning of the twisted wires to produce a dead cord (i.e. one which does not tend to untwist or curl when unrestrained). From the torsioning capstan the cord passes through a guide eye 14 which is rotated at the same speed as the cradle 11. Thus the excess twist inserted by the torsioning capstan is removed from the cord in passing to the eye 14. Instead of having two pulleys as shown, the torsioning capstan may comprise a single pulley around which the wires pass in at least one complete turn, similar to the lay pulley 10.

The eye 14 is a part of the take-up means in the apparatus, which comprises two rotating bell-like members (not shown) carrying two quadrant guides 15 (which may be parts of the rims of the bell-like members) which carry the wire in a loop or balloon around the take-up bobbin, and a guide 16 over which the cord is brought back to the axis of the lay plate 8, the die 9 and the cradles 11, 13, about which the quadrant guides 15 and the guide 16 are rotated. From this guide 16 the cord passes in the opposite direction to that of its original travel, in one or more complete figure-ofeight turns over a pair of pulleys -17 arranged with their axes perpendicular to the said axis about which the guides 15 and 16 are rotated. From these pulleys 17 the cord passes over a guide pulley 18 and a traverse pulley 19 to the take-up bobbin 20, which is driven about a stationary axis parallel to the axes of the pulleys 17. The pulleys 18 and 19 are mounted to rotate about axes parallel to the axis of bobbin 20, and the traverse pulley is traversed back and forth along its axis to lay the cord evenly upon the take-up bobbin.

FIGURE 3 shows the lay plate 8 used for producing a ten-wire cord as previously described. The lay plate 8 has two inner holes 21 spaced apart on a diameter of the plate and an outer ring of eight holes 22 arranged in arcuate groups symmetrically disposed in relation to the said diameter. After passing through the lay plate the wires are nested together at the die 9 with the eight outer wires arranged around the two inner wires in arcuate groups, allowing for a degree of float of the two inner wires, so facilitating the production of a dead cord. To facilitate threading, a lead slot 23 is cut in the lay plate 8 from its edge to each hole 21, 22.

For producing cords which have a distinct core comprising a group of wires, the core may be formed before the lay plate, if necessary by use of an extra preceding lay plate, and may pass through a single hole at its centre.

FIGURE 4 shows a pulley assembly for producing a seven wire cord from two groups of three wires and a single wire. Two pillars 24 and 25 are attached to the frame 2 6 of the machine and have three pulleys 27, 28, 29 and 30, 31 and 32 respectively, rotatably mounted on brackets on each of the pillars. The pulleys 28 and 31 are mounted so as to be rotatable about vertical axes whilst the pulleys 27, 29, and 32 are rotatable about axes inclined at to the vertical.

All six pulleys are arranged with their axes lying on a plane and approximately tangential to a circular locus on the plane. Between the pillars 24 and 25, also attached to the frame 26, is a pillar 33 which carries a pulley 34 rotatable about a vertical axis. The pulley 34 is adjacent to the centre of the circular locus in a position such that a wire in the groove 35 lies on the centre of the locus.

In use the pulley assembly replaces the lay plate 8 in the apparatus shown diagrammatically in FIGURE 1 with the plane bearing the axes of the pulleys perpendicular to the general direction of movement of the wires. Individual wires are passed around each of the pulleys 27 to 32 to contact the parts of the pulleys which are at any time remote from the central pulley 34, and partly around the pulley 34 to be withdrawn from the groove 35 perpendicularly to the plane passing through the axes of the pulleys.

It will be appreciated that it is not essential for the pulleys to be symmetrically arranged as is shown in FIG- URE 4 although this is desirable.

What I claim is:

1. A method for the manufacture of a wire cord formed from a plurality of single wires comprising the steps of winding the wires which are to form the cord in at least two groups each on a bobbin, the groups each comprising between two and six wires, drawing the groups simultaneously from the bobbins, separating at least some of the wires of the groups, laying the separated wires in the desired relation, twisting them together to form the cord and collecting the cord on a further bobbin.

2. The method of claim 1 wherein the groups of wires are wound over the ends of the bobbins to twist them together and are drawn off over the same ends to untwist them.

3. The method of claim 1 wherein the wires of the groups are continuously separated by passing them through separate guide means before laying them in the desired relation.

4. The method of claim 1 including the step of additionally twisting and then untwisting the cord before collecting it, to torsion the wires.

5. The method of claim 1 wherein the wires of the two or more groups are twisted together with one or more single wires to form the cord.

6. The method of claim 1 wherein one or more Wires are used as a core around which the remaining wires are twisted.

7. Apparatus for manufacturing a wire cord comprising means for mounting two or more bobbins, each having wound upon it a group of between two and six wires, means for withdrawing the group of wires from the bobbin when mounted on the mounting means, means for separating the wires of the groups, a twisting device for twisting the wires to form a cord and a take-up device for collecting the cord.

8. Apparatus according to claim 7 comprising guides to arrange the wires in a particular manner before they reach the twisting device.

9. Apparatus according to claim 8 wherein the guides are holes in a lay plate.

10. Apparatus according to claim 8 wherein the guides are pulleys in a pulley assembly.

11. Apparatus according to claim 7 comprising, in addition, a false twist unit arranged to increase the effective amount of twist of the wires so as to strain the wires after the wires have been led through a twisting device.

12. The apparatus of claim 7 comprising means for removing all twist from each group prior to the twisting device and a false twist unit arranged to torsion the twisted cord.

13. Apparatus of claim 12 in which the twisting device and the false twist unit each comprise at least one pulley mounted in a rotating cradle.

5 14. Apparatus of claim 13 in which the bobbin mounting means are stationary.

References Cited UNITED STATES PATENTS 2,037,506 4/1936 Ensinger et a1. 57161 X 2,124,864 7/1938 Weller 57-9 3,044,244 7/1962 Merritt 57-13 6 11/1964 Grafton 5718 X 12/1966 Vennett 57-15 X FOREIGN PATENTS 3/ 1902 Germany. 12/1928 Great Britain.

STANLEY N. GILREATH, Primary Examiner.

D. E. WATKINS, Assistant Examiner. 

